Cycle gurus, need your expertise please!

[bleed water]

Hi there,

This is my first post to the forum though I've come here many times seeking general advice which has been really helpful so thanks for that! My specific problem is that it seems I've thrown my tank into a cycle after medicating - I'm hoping it's only a "mini cycle" that I can regain control of without loss of life.
Here is some background--

About 1 week ago, I noticed one of my cherry barbs had a split in the tail and another had black tips on her fins. Looking closer I could see the fins of most of the c.b.'s were slightly affected. I guessed it was the start of fin rot due to poor water conditions, which was confirmed from testing as nitrates were higher than they'd ever been (80+ ppm; ammonia 0). I suppose this was from overfeeding and/or less frequent or smaller water changes in the last few weeks. Really, I don't think there was a major change to the maintenance routine so I am still a little perplexed about why. The only other change was that I'd recently wiped down the back of the tank and also rinsed (in tank water) and wiped down tank decorations to get rid of the coating of brown algae that's been growing for a long time. Normally, I let it alone in case it disturbs the balance but it had been affecting the plants more lately and I finally got tired of looking at it. I did leave some there and didn't go crazy with it....I don't know tho - could that cause the nitrates to spike?

So back to the fin damage- First did a few water changes to lower the nitrates. At my lfs they suggested melafix. They said to use the dosage on the instructions (10 ml/day for 7 days) and to take the carbon out. I put in a new filter bag without carbon. But because I have cardinals and I'm leery of additives in general, I stayed below the recommended dosage (more like 7 ml/day) and continued doing pwc's every other day. I got up to Day 6 but stopped a couple of days ago when I tested and found there was ammonia, which never happens. At that point I did about a 30% change and added about 25 drops of Prime, and that seemed to fix the problem temporarily at least. Then last night, the ammonia was up again so I did a 40% change and added 40 drops of Prime. When I tested today, it looked like the ammonia was at a higher concentration again than yesterday, and there was nitrite also, which I hadn't tested for earlier. Today I put carbon back into the filter. Fishes behavior appears mostly normal - maybe somewhat more stressed than usual but they are not gasping or hiding. I am not sure if the fins have improved but they are not any worse.

I need to consult with some folks more knowledgeable than me to get some help with 2 major questions because at this point I'm starting to feel like I'm just guessing!
1) what should I do next? (should I continue trying to manage with water changes? Is it ok to keep using Prime like this? Anything else I can do)
2) why did this happen? (did melafix kill the beneficial bacteria? can removing the algae cause a nitrate spike?)

Thanks so much for reading...any and all suggestions are very much appreciated!!

Marisa

Current Parameters/Additional Info:

Ammonia: 0.50 and rising
Nitrate: 10-15 ppm
Nitrite: 0.25
Tank: 20g long, 1 year old
Population: 8 cherry barbs (5 F/3 M - 2 of the females are massive and look like they are on steroids) and 7 cardinal tetras, nothing added in last 4-5 months
Maintenance: Once per week 25% water change and "quick" gravel vac. More thorough vac (removing everything) every few weeks

The amount of fish in the tank is a little more than I am comfortable with to be honest because there really isn't much room for slipping up on maintenance at all. Up to this point I haven't had any big problems or lost any fish though.

[Jweickum]

Ya it's sounds like you restarted your cycle. I would do daily pwc up to 50% to keep your ammonia below .5

All plant life uses nitrates as nutrients which lowers your nitrate levels. Removing all that algae means removing plant material. Do you have any other plants in there? I personally don't use any a whole lot of chemicals so I don't know about prime or melafix. But I use caribsea ready water which comes with some BB and that worked really nicely for me. It's like 6 or 8 bucks for 2.5 gallon container.

I also now have a really handy container to hold my pretreated water for top offs.

Well that's all I have for advice. Good luck.

You can pm me for more questions if you want.

[Mebbid]

If you are still seeing nitrate production then it should only be a mini cycle and should clear up before too long. The reason that you are getting ammonia readings is because you inserted a new filter bag. Almost all of a tank's bacteria is located in the filter itself, so removing that is, in effect causing a mini cycle all on its own. Just keep up with the water changes and it all should take care of itself over time.

I use melafix quite often and have never seen it effect my biological filter. I would go with the full dose on the tank as it is a fairly weak curative.

Prime is a fairly safe additive to use so I wouldn't worry about it too much.

Also, removing the algae isn't going to have any noticeable effect on your tank readings. They take up such a small amount of nutrients that it wont make much of a difference at all.

[bleed water]

Thanks for your responses &-somehow getting through all the wordiness in my OP. Don't know if I could've been that patient!

Anyway, makes sense. I'd hoped the nitrates were a good sign, but hearing it reassures me. I'd say the tank is medium planted, so I guess that helps in some ways too.

Yeah I've heard melafix is pretty mild. Lots of people say they use it with no problems. I assume taking out the filter media at the same time was too much since it is a mild antibacterial. Smells pretty strongly like Vicks vapo rub though which made me sorta nervous. And with all the things that could possibly be screwed up by a noob, i figured it's pretty likely that at least one thing will go wrong on the first try of doing anything like this (Like taking out the filter media!) So under dosing gives me a way of hedging my bets...an irrational way for sure, since it probably doesn't do much of anything if you don't use enough, right? But that kind of caution sometimes works out for me in the end

Think I should try dosing mela by regular instructions after mini cycle - but leaving in media - if fins aren't healed yet? Or wait a while? They still have a mild case only. I'd like to keep things as natural as possible, but I don't know if fin rot is likely to go away on its own or how long it takes.

[Mebbid]

Assuming the old filter was kept wet; I would just reinsert the old filter and then continue dosing the melafix as directed. If your carbon is a month old or more it isn't doing anything beneficial for your tank so it shouldn't pull any of the medication out of the tank. If the old filter has had a chance to dry out you might as well keep using the new filter as the old BB will have all died off.

Also, on a side note if you don't dose the directed amount of any kind of medication it will most likely minimize if not completely negate any effect the medication might have.

[jlk]

Welcome to AA!!!

I don't think melafix or any actual meds are necessary here (yet). Water quality issues are the most common cause of fin rot- addressing them will affect a cure in the majority of the cases. The excessive nitrate levels were the likely culprit as they inhibit a fish's ability to assimilate oxygen thus affecting all bodily functions including compromising the immune system. Excess nitrates will also greatly increase stress levels. Stress is a major culprit in any fish ailment. I honestly would work on bringing your nitrates under control (20ppm or less) and keeping them there in addition to some extra water changes. If their fins do not show marked improvement over the upcoming week, then actual meds may be necessary to bring the fin rot under control. Keep us posted!

[bleed water]

Thank you, glad to come out of hiding! Interacting is so much more interesting.

But ugh...when I tested this morning, the tank had jumped to a scary 4 ppm ammonia. Nitrite was back down to zero. I wasn't expecting that much of a jump in a mini cycle but maybe this is normal. (is it?) Amazingly everyone was easy to find and they all looked okay, swimming around and occupying all parts of the tank. After prime and water change we're back down to 0.25 but I can't expect it to stay there for long.

mebbid, thanks for the tip on the filter. I think it's dry by now unfortunately..but still useful knowing that in the future maybe I should keep some old media in a workable state for occasions like these.

Well I'll keep a close eye on the fins but for now it looks like getting through this new cycle is going to be my big priority. Probably not a good time to make any new changes. I don't see any additional damage thankfully. They've definitely been hardy little fish but I know the stress of all this can't help matters.

[bleed water]

After a scary ammonia spike on Saturday followed by several large water changes, I think I'm almost in the clear. This evening's readings were nitrite 0, ammonia < 0.25, nitrate 5. Relieved! : )